This cover is the first edition version of the book cover. I personally don't like it very much, the shadowing of the title seems very awkward and greatly reduces the legibility of the word "THE." The choice of colour also seems quite jarring. I do like the rough texture though, as it reflects the gritty subject matter and storyline of the book.
This cover was used for the book in the 1980s. I feel like this cover is much stronger visually, although not as good as it could be. The typeface for the title of the book seems to have a very 50s feel to it, which is a decade late for the novel. The image of the man however, has a very strong visual impact in the way it has been cut off, creating an air of mystery, matching the tone of the book.
This is the current cover of the book used by Penguin. I think the use of silhouettes is very effective, creating a very unique atmosphere. The Saul Bass inspired typography also gives it an unusual and interesting feel. I'm not the biggest fan of the colours used but it make sure it stands out against the crowd.